A . New words and expressions . Fill in the gaps with words given in the box . Change the form where necessary . average diabetes diet extend gene immune lengthen remain 1 . The lady had stomach trouble and had to follow a strict _. 2 . It s safest to _ a good distance behind in case the car in front suddenly stops. 3 . His mental faculties fall somewhat below the _. 4 . Fruit trees _ out over the farm fences。 5 . _ is a medical condition in which someone has too much sugar in their blood. 6 . She began to walk faster but he _ his stride to keep up with her. 7 . A _ is a part of cell in a living thing that controls what it looks like how it grows and how it develops. 8 . Once we ve had the disease,we're＿for life.